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41.
The acquisition of cognitive skills often depends on 1 of (or a combination of) 2 processes, the execution of an algorithm, and the retrieval of problem instances. This study examined the effects of age and repetition of problem instances on the production and verification of solutions to 2 serially presented sets of alphabet arithmetic problems. Analyses of the parameters derived from power-function fits for individuals revealed age differences favoring young adults in improvement span, learning rate, and asymptote. For both age groups, the beneficial effects of repetitions on 1st-set response times were attributable to algorithmic speedup and to the retrieval of instances, whereas improvements in the speed of 2nd-set response times were attributable primarily to item retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
Two experiments examined long-term repetition priming in data entry. In each experiment, participants entered 4-digit numbers displayed as either words or numerals, and responded with digits (Experiment 1), or either digits or initial letters (Experiment 2). At test 1 week later, they entered old and new numbers, with the format changed for half of the old stimuli. Implicit memory was evidenced at test by faster entry of the old than the new numbers, regardless of whether the numbers were in the same or different format, suggesting that the abstract numerical meaning, not the surface form, contributes to repetition priming. Numbers presented as words in training had an advantage over numbers presented as numerals, regardless of response format, implying that type of processing also contributes to the effect and ruling out an explanation based on time spent processing numbers in word format. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
In the current study, the authors used an immediate repetition paradigm with pictures to observe whether repetition enhances word production in bilinguals. In Experiment 1, participants were asked to name pictures that were named previously in the same language (Spanish-Spanish or English-English) or in the opposite language (Spanish-English or English-Spanish). Results revealed a repetition effect both within languages and between languages. Furthermore, there was an asymmetry within language, with repetition priming being larger in Spanish than in English. Experiments 2 and 3 revealed that lag interacted with language for both within- and between-language priming. However, lag resulted in a decrease in the asymmetry for within- but not between-language priming. The results are consistent with the view that within- and between-language repetition priming are mediated by different mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
Neill W. Trammell; Neely James H.; Hutchison Keith A.; Kahan Todd A.; VerWys Christopher A. 《Canadian Metallurgical Quarterly》2002,28(1):137
In these experiments, 2 letters were presented sequentially to the left and right of fixation, followed by pattern masks. Report was cued by spatial location (Experiments 1a, 1b, 2, 4, and 5) or temporal position (Experiments 3, 4, and 5). In all experiments, 2 identical letters on a trial resulted in reduced accuracy of report (repetition blindness; RB) for both the 1st and 2nd presented letters. This decrement was greater for the 2nd letter if subjects expected temporal cues, but tended to be greater for the Ist letter if they expected spatial cues. Analyses of errors and responses on catch trials indicated no bias against report of repetitions, and the repetition decrement did not interact with output order. The data are inconsistent with both type-refractoriness and memory-retrieval accounts of RB. A modified version of N. G. Kanwisher's (1987) token-individuation theory is proposed to account for the results. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Reports a failure to find a repetition deficit in recall following the rapid serial visual presentation (RSVP) of words within sentences, using adjectives rather than nouns as the critical items. In a series of experiments that ruled out participant and procedural differences as the source of the failure, both word class and list context were found to moderate the repetition deficit, but grammatical necessity did not. The presence in the list of sentences in which the repeated adjectives were separated by more than three words not only eliminated the repetition deficit for the recall of those sentences but also for the recall of sentences in which the repeated adjectives were separated by three or fewer words. However, although substantially reduced, a repetition deficit with noun-based materials was still found in this list context. Matching the adjective-based sentences with the noun-based sentences in sentence length and position of the critical items revealed that the moderating effect of word-class on the repetition deficit was mediated by the biases in sentence structure that using different word classes tend to induce. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
The aggressive response of male bullfrogs (Rana catesbeiana) habituates with repeated broadcasts of acoustic stimuli simulating a new territorial neighbor. The effects of stimulus repetition rate and stimulus intensity on bullfrog aggressive responses were tested in a field experiment designed to test the assumptions of a dual-process theory of habituation. Synthetic advertisement calls were broadcast at 2 repetition rates and 2 intensities in a factorial design. Bullfrogs were more aggressive at the higher stimulus intensity at both repetition rates. Aggressive responses habituated more slowly at the higher stimulus intensity and slower repetition rate compared with other treatments. Several biotic and abiotic factors had small or negligible effects on aggressive responses. Although consistent with the operation of 2 opposing processes, habituation and sensitization, the data provide only partial support for the assumptions of dual-process theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
陶瓷微滤膜回收偏钛酸过程中反冲技术研究 总被引:6,自引:1,他引:5
对陶瓷微滤膜加嘏偏钛酸颗粒过程中应用反冲技术控制膜污染进行了研究,观察了反冲压力、时间和周期对反冲效果的影响,确定了合适的反冲条件;比较了有无反冲存在下,操作参数对膜通量及其下降情况的影响;考察了反冲过程的重复性;探讨了反冲过程的机理,对陶瓷膜回收偏钛酸过程中反部诉成功及此的过程的工业化应用有重要的意义。 相似文献
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